زهراء جاسم جابر الطالقاني

Abstract:: There has been a great development in information technology and methods of sending it via the Internet, but these developments expose the information transferred to violations of its security. To maintain information security, steganography and encryption are used. Hiding technology in multimedia, such as audio, video, text or pictures, provides an ability to protect information. Digital video is one of the most common data embedding media for its high ability to hide sensitive data. Where many methods have been proposed to hide the data in the video to prevent it from being seen by unauthorized persons. This paper proposes a new approach to hiding data in video by using two bitand and bitor processes without using the well-known LSB algorithm in the hiding method. In addition, confidential information is first encrypted using a genetic algorithm by which the encryption key is generated, which increases the strength of the proposed work. The experimental results showed that the used method is effective and safe as it provides a PSNR of 63, which makes the embedding capacity high

Abstract: The science of information security has become a concern of many researchers, whose efforts are trying to come up with solutions and technologies that ensure the transfer of information in a more secure manner through the network, especially the Internet, without any penetration of that information. Due to the importance of digital data sent between the two parties through an insecure channel. As a result, there are many technologies and methods that are currently used in information security, including steganography and encryption. This paper proposes a safe method for text and audio files by encrypting them using the RC4 algorithm that relies on the chaos system. This system generates chaotic values that increase the randomness of the key and thus difficult to break. Then use the embedding technique in the color or grayscale images using the LSB sequential algorithm. I relied on hiding in the edges of the image, which were areas of strength where the change was not noticeable. The results showed a high ability to include data, as the PSNR scale reached more than 50, and the retrieved data was obtained without errors.

Abstract Plagiarism is a critical problem that appears in most universities and researchers. It is a challenging task, especially in case of highly inflected and rich languages such as Arabic. In this paper a proposed reliable approach for plagiarism detection in Arabic language, designed and implemented using an efficient and quick way. Themain idea is to use simple Information Retrieval system (IR) to compute the percentage of grams of plagiarized text which is difficult without using exact match algorithm. The proposed method consists of four main stages: (i) Pre-processing, (ii) Lexical semantic manipulation, (iii) Indexing with n-gram and (iv) Calculating the percentage of plagiarism. The system calculates the percentage of plagiarism directly from the intersection of its grams without using any exact match algorithm. The extracted percentage is done in two ways: (i) percentage of plagiarism in suspicious document (a file in data set) and (ii) percentage of plagiarism in a file in data set (to suspicious file). Then Precision, Recall, F-measure and Error rate are evaluated. The proposed method is compared with a selected method (winnowing algorithm), using the same data set, an improvement in percentages of error rate were recorded. In case of execution time, the proposed method is four times faster than winnowing algorithm. Also, semantics manipulation is added to improve the proposed plagiarism detection system. The results of the proposed method are 0.853624, 1, 0.889991 and 0.022048 for precision, recall, f-measure and error rate respectively, while the results of winnowing algorithm 0.666518828, 1, 0.720509265 and 0.043987806 for precision, recall, f-measure and error rate respectively.

16 ISSN: 2005-4238 IJAST Copyright ⓒ 2019 SERSC Lexical Semantic in Arabic Plagiarism Detection Using Winnowing Algorithm (Word Level) Zahraa Jasim Jabir1, Ahmed H. Aliwy2 1,2Department of Computer Science, Faculty of Computer Science and Mathematics, University of Kufa, Najaf, Iraq Abstract The Plagiarism is an illegal electronic crime for violating the rights of authors and publishers. In the indexing process, fingerprint algorithms are used. We extracted fingerprints for every five words by hash function. The winnowing algorithm was used on words instead of letters for selecting the fingerprint and to reduce the size of the index. Winnowing algorithm used with synonym replacement and without synonym replacement to compute the percentage of grams of plagiarized texts, done in two ways: (i) percent of plagiarism in suspicious document (a file in dataset) and (ii) percent of plagiarism in a file in dataset (to suspicious file). And then the Precision, Recall, F-measure and Error rate are estimated. The results for winnowing algorithm (with synonyms replacement) in the first methodology are (precision, recall, f-measure and error rate) were (0.84861, 1, 0.889206 and 0.034461) respectively, and in the second methodology are (0.852961, 1, 0.892954 and 0.030137) for (precision, recall, f-measure and error rate) respectively. The results for the winnowing algorithm (without synonym replacement) in the first methodology are (0.849207, 1, 0.889764 and 0.034452) and in the second methodology are (0.852554692, 1, 0.892920502 and 0.030153138) for (precision, recall, f-measure and error rate) respectively.